Postcards From Atlantis
by marginaliana
Summary: Dear Amy and Rory. Weather continues fine...   Written for the who reversebang challenge on LJ. Request: 11th Doctor, River, and Jack have an archaeological adventure.
1. Prologue

He landed the TARDIS silently on the corner a few streets behind Amy and Rory's house. He left the parking brake off, for once, in part because he wanted to surprise them, but also because he thought if he actually intended to lie low for a while, not making a showy entrance every time he visited somewhere was probably a good start.

The back fence was short enough to climb over with only a minimal run-up, and the lock on the french door clicked open after only a split second's buzz from the sonic screwdriver.

River was in the kitchen, writing carefully in her little blue book. Two steaming cups of tea sat waiting on the table. Without looking up, she pushed one gently in his direction. The Doctor pouted for a moment, then gave it up as a bad job and dropped into the closest chair.

"How'd you know I was coming tonight?" he asked. He leaned back, draping his legs over the corner of the table, and took a sip of tea. It was good – just the way this version of him liked it.

Now she did look up, smiling. "It was the right kind of sky. Hello, Sweetie."

"Hello, River." He took the opportunity to look at her, really look at her – after all, she'd had years to study him – perhaps a lifetime. "When is this for you?" Rather late in her timeline, he thought – there were new lines around her mouth, and the faintest hint of grey in her hair. Her eyes looked tired.

"After the Byzantium," she said. "A bit disconcerting to be introduced to Amy for the first time, so I came here afterwards. I've missed them."

He nodded.

"You?" she asked. "Utah?"

When he nodded this time, her face softened. "You'll want that tea, then."

They were married now, he remembered. Married, and in timelines when both of them knew it. He was surprised to discover himself happy about that. But thinking about timelines made him think about the Library. She'd be going there soon; she'd meet a man who didn't know her; she'd die.

"Time can be rewritten," he'd said to her then.

"Not those times," she'd said. "Not one line, don't you dare."

Before he could grapple with that memory, though, there was the sound of feet thumping down stairs, and then Amy appeared in the doorway, wrapped in a bathrobe and with her hair wet. "River, do you need anything before we— Hey!"

The Doctor swung his legs down off the table in preparation for a hug, but got a whack on the shoulder instead. "Ow! What was that for?" But Amy was already plopping down into his lap and hugging him, so rather than get a mouthful of hair he decided not to argue further. He patted her shoulders once, gingerly. Over her shoulder he could see River, grinning..

"That was a dirty trick you pulled," Amy said, pulling back enough so that she can look at him. "A low down, dirty trick." She paused. "But I'm glad you're not dead."

"Me, too," the Doctor said, and then, "It was necessary. But I am sorry."

"Amy?" More feet thumping. "Does River need any— Hey!"

Rory's look of surprise was even more satisfying than Amy's. Amy climbed out of the Doctor's lap, and he let himself be hauled to his feet and hugged vigorously once more. When Rory stepped back, the Doctor turned to River, who was regarding them all with indulgent pleasure.

"Going to make it three for three?" he said, but she was already standing up, stepping forward, hands sliding up his lapels. iOh, yes, married,/i he thought, and then her lips were on his, warm and soft and sweet.

When they parted he stood stock still, blinking stupidly for a long moment.

"You two should have a honeymoon," Amy said. The Doctor looked at her, startled, and heard River start to laugh, low and throaty.

"Eager to get rid of me already?" he asked.

"What? No, you big doofus," said Amy. "But you've just got married. Or, I mean, haven't you? Actually, when is this, you know, for you?"

River was still laughing. The Doctor gave her a quelling look, which didn't work in the slightest.

"Yes," he said to Amy. "That is, yes, married, but I don't think—"

"You made sure iwe/i had one," Amy said. Rory made a pointed noise in the back of his throat, and she qualified hastily, "I mean, we did almost crash into an alien planet and die, but that was okay. Spiced it up a bit."

"I—" the Doctor said, and then stopped. He had been intending to say, 'I don't do honeymoons – too domestic.' But River was right there, smiling and saucy and very, very appealing, and anyway a honeymoon didn't _have_ to be domestic, did it? "I think that's a good idea, Pond," he said instead, and had the satisfaction of seeing River look genuinely surprised for the first time in a long while.

* * *

><p>In the morning they left the Ponds lounging in the garden and went shopping for groceries, then carried their bulging bags of fish fingers, Bird's custard powder, and Jammie Dodgers back to the TARDIS. When everything had been stowed away, the Doctor checked a few instruments, verified that nothing in the immediate vicinity seemed to need looking after, and turned to River.<p>

"Where to?" he asked. It wasn't a test – or, not exactly. But he did want to see what she'd choose. Whether it would be a typical honeymoon spot, romantic and relaxing and _boring_, or somewhere that needed him, his brain and his hands, somewhere that needed saving.

"Hmm." River thought about it.

The Doctor started fiddling – tightening the wires connecting the atom accelerator and the typewriter, though they didn't really need tightening – and watched her via her reflection in one of the console screens. She had one of those secretive little smirk-smiles on her face, an expression that was at once absolutely infuriating and strangely attractive. It was an expression that made him _feel things_, though he didn't dislike it as much as he'd thought he would.

River cocked her head for a moment, and then her lips quirked up into a proper smile. She stepped up to the console and ran her hand up the pillar, once, tenderly. "I think we ought to let her decide."

The Doctor beamed. It was a good answer. "Right," he said, and sidled around to the navigation segment of the console. "Pick a number."

"Twelve thousand, four hundred and seven," River said, coming to stand beside him. "Why?"

He punched it in. "No reason." River laughed. "Ready?" he asked.

She reached for the throttle handle and he reached for the time rotor lever. "Ready," she said.

"Geronimo!" They pulled together.


	2. Day 1

_Dear Amy and Rory,_

"What are you doing?" River folded herself gracefully down to sit beside Doctor on the broken length of marble column he had rolled up near the fire. She tilted her head over his shoulder to peer at the object in his lap. Her voice was low and her warm breath gusted against his ear. He could smell the faint cardamom scent of her hair.

"Writing a postcard. Weeeellll, a post card-ish, er, thing." He flicked off the sonic screwdriver and passed over the flat piece of slate, now etched with his greeting in small, even letters. "I found it while you and Jack were scavenging for firewood."

"Good idea," River said. "They'll be sorry they missed this." She hesitated for a moment. "Well, Amy will, anyway."

The Doctor grinned. "Good point."

River passed the piece of slate back, then leaned her head down to rest on his shoulder. The Doctor felt his hearts beat oddly for a moment, out of rhythm, as if something had reached into his chest and squeezed. "River," he said softly.

"Mmm?"

He hadn't actually planned anything to say beyond her name. "Nothing." He flicked the screwdriver on again and resumed writing.

_Weather is fine. We ended up on a rather interesting island. The trouble is..._

* * *

><p>They stepped out onto a flat expanse of beach, sand the same bright gold as the Heart of the TARDIS. Water on three sides of the beach stretched out, rough-waved, to the horizon. On the fourth side the sand ran for several hundred yards, then gave way to a series of dunes of increasing height. And beyond the dunes…<p>

"Oh, my," said River.

Beyond the dunes was a city, or the remains of one. White columns and pyramid-shaped turrets loomed over stone buildings with empty window-holes and hollow doorways. Roads and paths swirled and darted from building to building, broken occasionally by terraces and public squares. There were few trees visible, trunks sagging and the dark green fringes of their leaves clinging limply to roofs as if they'd been wrung out like sponges. The later afternoon sunlight made everything glimmer, and the city seemed to be deserted.

The Doctor pulled out his sonic screwdriver, using a quick flip of his wrist to open the sensor claws. "Hmm," he said. "Earth, 2065. More specifically…" He stuck out his tongue. "The middle of the Mediterranean Sea." River raised her eyebrows, and he clarified, "Spain is about 300 miles, er, that way." He indicated the direction in front of himself with a pointed fingertip. "And Italy over there, a bit closer." Another fingertip, this time pointing to his right. He flicked the sonic closed and put it back in his pocket. "Which means this place—"

"Is not supposed to be here," River finished. He gave her an approving look.

"Right in one." He straightened his bow tie. "Shall we?" She took his arm and they stepped forward across the sand.

A few minutes of walking found them stepping onto a crumbling stone walkway at the edge of the city which seemed to have functioned as a sort of promenade. It was gracefully designed and the white expanses of stone gleamed in the sunlight, each block's sides and corners worn smooth. Here and there were jagged piles of stone and metal and plastic, grouped together in heaps. Some of the materials had clearly been made with a purpose, too regular to be naturally formed, but others were just rocks of every possible color, purple and mud-earth and crimson and grey-green and gold, some sparkling and others dull.

Something about it was unsettling. Perhaps it was the emptiness of the place, the Doctor thought. But that didn't ring true. He'd seen enough ruins in his time to know what they were like, and the knowledge that some civilization had come and gone had long since ceased to disturb him. As they walked further into the empty city the feeling of wrongness intensified, like a tickle in a place he couldn't quite reach – not painful, but dull and persistent – and he realized that the sensation was coming from somewhere outside himself.

"Do you feel that?" River asked abruptly. "There's something— Itchy?"

"Yes," said the Doctor. He looked at her sharply. Whatever it was, it was affecting both of them. Although that didn't tell him anything useful, really, since he had no idea what sorts of things she could sense. She'd given up her regenerations, he knew that much, but that didn't make her human. "River..."

"Stop worrying, Sweetie," she said with a smile. "We're on holiday, remember?" She kept walking, and since she still had hold of the Doctor's arm, it gave him little choice but to follow, off the promenade and into the city streets.

The more they saw of the city, however, the more questions it presented. It showed all the signs of a catastrophic disaster: doors hung open, some splintered beneath the weight of fallen columns, and household objects were strewn about – broken shards of clay pottery, a small electronic toy with no screen left, clocks with smashed cases, torn blankets, a square, marble-topped table. Any of those could have come from a city like this. But there were other things, things that didn't match at all – the third left arm from a suit of 48th century Hamian armor, badly dented; a korintol, only missing three of its four hundred and seventy keys; a plastic box in the shape of Elvis' face that said 'Happy 200th Birthday, Elvis – 1/8/2235' on it; a statute of the Posicarian god Terlipsis, who looked a bit like a gecko in a monk's habit with a bad case of dehydration. None of that belonged here.

"Where could it all have come from?" River asked, pausing to bend over what looked like a some sort of medical device. After a moment she established it was broken and straightened up, hands on her hips. "My first thought was, well. The korintol, that replica of the Lona Venus – could be a collection. Whoever lived here went around picking up stuff that interested them. But some of this... it's just junk."

"Mm, yes," said the Doctor, nudging a pile of wet cloth with the toe of his shoe. "Most of it, even." He caught sight of an Olabrian joy-luck crystal and wandered over to peer at it. "Ooh, now what's this? Shiny, this is. I wonder—"

There was a booming noise, somewhere off to their left, and then the high whine of a sonic blaster. The Doctor whirled, listening hard, and heard three more blaster shots, then a voice shouting, not quite intelligible. "Come on," he said, and started to run.

* * *

><p>The Doctor paused, rubbing his thumb over what he'd just written to smooth out the edges of the letters. On the other side of the fire Jack had spread out his coat to dry, and he was in the process of emptying out his pockets to see how much water damage the contents had suffered.<p>

_We ran into an old friend of mine. Well, I say ran into. I mean almost literally ran into. What happened was..._

* * *

><p>The building was dark, the walls and floor cracked and pitted. The debris continued here, too, though a path had been crudely forged through it, enabling them to move a bit more quickly. The strange, itchy feeling intensified suddenly and the Doctor stumbled, just barely catching himself before he tripped over yet another pile of rough-edged stones and bits of old circuit boards. River slid through the doorway ahead of him, out of view.<p>

"Hey!" he heard her say. "Hold it!"

The Doctor scrambled through into the next room and came up against River's back, just inside the doorway. Her blaster was out, its barrel evenly lined up with that of an almost identical weapon, held in the steady hand of someone very, very familiar.

"Jack!" said the Doctor, feeling relief sweep over him. That explained rather a lot.

"Have we met?" Jack asked, his eyes still locked on River.

"Oh, for—" said the Doctor, and then, "Put those away, you two. What is it with you humans and your guns?"

"Doctor?" said Jack. His gaze flickered over and the blaster wavered a little.

"Well I'm not _Mickey Mouse_," the Doctor said tartly. "Of course I'm the Doctor!" He felt a tiny bit offended not to have been recognized, but a moment later he rubbed his chin and realization struck. "Oh, yes, yes, yes, I suppose you haven't seen this face yet. New face, new voice, the whole workup. But it _is_ me."

"Of course it is," Jack said, his stance relaxing a little. "Should've known you'd turn up and send everything to the dickens." He lowered his blaster slowly, then grimaced and thrust it back into its holster. "Damn it. I don't suppose you were the ones taking pot shots at me."

"When I'm shooting at you, you'll know it," River said, but she was holstering her blaster, too, and giving Jack a speculative look.

* * *

><p>The memory made the Doctor smile a little.<p>

_Once I got them to stop playing 'who's got the biggest gun' they got along famously..._

* * *

><p>Jack, of course, couldn't let the conversation advance any further without flirting. He gave River a blinding smile and inclined his head. "Captain Jack Harkness, at your service."<p>

"Doctor River Song," she said, and held out her hand. Jack took it and lifted it to his lips gracefully.

"A doctor as well?" Jack said. "Skilled _and_ beautiful. The Doc here sure knows how to pick the good ones." It was a terrible line, but coming from Jack it was almost convincing. River laughed, and it was a pleased noise, as if she were flattered.

The Doctor discovered he was grinding his teeth. "Jack's the weird thing," he said to River. "That horrible feeling."

The smile dropped from Jack's face, and the Doctor immediately regretted his words. River was glancing between the two of them, her eyebrows raised. "Ah," she said finally. "Well, a little tingling sensation can be enjoyable, you know." The attempt at innuendo didn't quite work, but it was enough to make Jack's shoulders loosen somewhat.

"Sorry, Jack," the Doctor said, contrite.

"Forget it," Jack said. "Not like I didn't know that." He slung the smile back onto his face. "So what's a Time Lord like you doing in a place like this?"

* * *

><p>The memory made the Doctor feel ashamed all over again. He hadn't done well by Jack, not today and not for a long time. It was just that Jack frightened him, partly because of what he was (wrong, impossible) and partly because of <em>who<em> he was (a reminder of so many past mistakes). But the Doctor knew it wasn't fair of him to keep Jack at arm's length, not when Jack had done so much for him. The trouble was that he didn't think he knew how to do anything else.

He shook his head and started writing again, trying to distract himself.

_Unfortunately, Jack doesn't know why the island is here, either. Though River at least figured out one important detail..._

* * *

><p>"Oh, you know," said the Doctor. "Traveling. Here and there, there and here, a little bit of every which where. Tell me about this island, though. Bit unusual. Well, actually, very unusual. Shouldn't be here, though I expect you know that already or you wouldn't be here."<p>

Jack sighed and cleared off the surface of a table with a sweep of his hand, then sat on it gingerly. "It turned up a couple of days ago, overnight. Fishermen from the area reported – one day no island, next day, poof. Island. No one saw it come down, either – no sensors, no eyewitnesses, nothing." He tilted his head back, as if looking up would offer some clue about the city's origins. "Torchwood checked it out – _safely_, from a distance. No sign of anything radioactive, time-traveling, or even alive. No artron energy. I'm only here to double check those readings, make sure it's safe before they send in the research team."

"Hmm," said the Doctor. The reminder that Jack worked for Torchwood was faintly unpleasant, though this was 2065, so they were almost respectable now. "Interesting, interesting, interesting," he said. "Bit of a mystery. I love a good mystery. I met Agatha Christie once, did I ever tell you that? Brilliant woman. I helped her out with a bit of a wasp problem."

"Wasp problem?" Jack mouthed at River, but she just shook her head.

"Vespiform," said the Doctor. "Very sad story. Anyway, the city. It must've been shielded when they brought it in. There are plenty of species that could have arranged it. Can't think of any who'd have had a good reason to, that's the tricky thing." There wasn't much room to pace, so he contented himself with rocking back and forth from one foot to the other, turning slowly in a circle. "Why bring a city here, shielded, and then just leave it? Why do that?"

River made a noise in the back of her throat, and smiled when they both turned to look at her. "Boys, boys. You're missing the obvious."

"What?" said the Doctor.

"What?" said Jack.

"It didn't come down," she said, waving a hand to indicate the debris that surrounded them. "It came _up_."

* * *

><p>The Doctor let his eyes wander from the piece of slate to River's hands, folded neatly in her lap. He wondered if she sat like this in prison – patient, enduring, thinking she deserved it – until some sign appeared to tell her she was needed. He could imagine her, then, rising from her cot with fluid grace, letting herself out of the cell with quick, neat movements. She was amazing. Though he still wasn't too fond of guns, he had to admit that seeing her shoot was oddly thrilling. It wasn't the gun – it was the competence with which she used it.<p>

_Of course, after that we got a little bit sidetracked when someone started shooting at us..._

* * *

><p>Jack led them away from the building towards a camp he'd set up on the far side of the city. The sun was rapidly going in, and the brightness was fading from the city streets, replaced with the gray-blue aura of dusk. The Doctor hung back, eyes scanning over each of the buildings they passed. Something about the city was nagging at him, something familiar. Many of the buildings had doorways flanked by tall, white columns, decorative rather than functional, but there was a pattern to them that he couldn't quite put his finger on. The trouble was that many of the columns had collapsed or been buried under other bits of rubble, so whatever pattern they formed was half-obscured by the chaos.<p>

They were just crossing a square when a bolt of electricity sizzled out from the alley between two nearby buildings. It caught Jack directly between the shoulder blades, and he dropped like a stone, tipping over the edge of the fountain to land face-first in the water. The Doctor reached for him instinctively, then felt the fabric of time warp and twist, briefly unraveling around Jack and then slowly beginning to knot together again. It was enough to remind him that he didn't need to worry about Jack, not now, so he left him where he was and ducked down by the rim of the fountain. River was already there and returning fire, arm straight and sure as she fired through the cascade of water into the shadow of the alleyway. Another sizzle of electricity came at them, but hit one of the water spouts and fizzled into a shower of sparks. River fired again, but there was no return shot, and after a moment the Doctor heard movement, further off, as their assailant retreated.

He reached down and hauled Jack's body to the surface.

"Oh, god, Jack," River murmured. She sounded wrecked, and the Doctor hastened to reassure her.

"No, no, no, no, no," he said, shaking his head. "He'll be fine. Totally fine. That's the, you know, his odd thing. He doesn't stay dead." He'd barely gotten the words out when the knot in time finished tangling itself back together and snapped tight. Jack gasped, sucking in air, and sat bolt upright.

"Easy, Jack," the Doctor said. "Easy. You're okay."

"Fuck," said Jack. "I hate electrocution. My toes will be tingling for hours." He looked down. "And I'm wet. Do you have any idea how long it takes to dry this coat?"

River's mouth was hanging open a little. Then she shook herself once, briskly, and said, "We should get under cover, Sweetie. No telling how many of them there are, or if they're coming back."

"Good point," said Jack. He gave the Doctor a saucy wink and held out his hand. "Help me up, _Sweetie_?"

* * *

><p><em>Well, must dash – not really, I mean, not right now, there's no impending disaster right this instant, or people shooting at us, or the world ending, but I'm running out of room to write on. Blimey, your language does take up a lot of space.<em>

The Doctor paused. "River? Want to write anything?" She didn't answer, and when he twisted his head sideways to look at her, he discovered she was fast asleep, head still pillowed on his shoulder. Jack's chuckle told him that the other man had noticed his predicament. The Doctor glared at him half-heartedly, but this only made Jack laugh again.

"I like the new face, by the way, did I tell you that?" Jack said, his voice pitched just loud enough to carry. "It's cute. A bit wonky, but cute. Not sure about the bow tie, however."

"Bow ties are cool," the Doctor said automatically. "And I am _not_ cute."

"Whatever you say," Jack agreed, but he was grinning like a loon. "Why don't you sleep now? I'll wake you in a couple of hours."

Normally he would've said that he didn't need to sleep, but being around Jack was exhausting. That ever-present sense of wrongness meant that some part of his brain was constantly on-edge, wary, watching. Plus River was here, warm and soft and—

He didn't actually have to justify this to himself, the Doctor realized. "Thanks, Jack," he said, and he tried to infuse it with all the things he didn't – wouldn't, couldn't – say. Something in Jack's face changed as he registered the implication.

"Any time," he said, and he sounded like he actually meant it.


	3. Day 2

_Dear Amy and Rory. Weather continues fine.._

"Another postcard?" River stood with the setting sun at her back, and when the Doctor looked towards her he found the curly halo of her hair now lit with a fading orange-gold glow. Behind her in the distance was the long stretch of the sea, waves lapping towards them with increasing swiftness.

"Er," he said, and then shook himself. "Isn't that the traditional thing, when on holiday?" This time he was writing with pen on paper, though the paper showed the characteristic waviness that meant it had been soaked wet and then dried unevenly. The reverse side of the sheet was an advertisement for something called "Madam T'pel's Fascinating Elixir," and contained an illustration that was certain to shock Rory (and amuse Amy), which was why he had chosen it. "Having a wonderful time, wish you were here?" He paused, considering. "Well, perhaps not."

The rocks beneath them shifted, the water rising a fraction of an inch higher through the shoreline's cracks and crevices. The Doctor looked down at his shoes, now wet through the toes, then braced the sheet of paper against his palm and continued writing.

_The island this morning was even more beautiful than yesterday…_

* * *

><p>The night had passed quietly, and when the Doctor woke it was to the smell of Jack cooking breakfast. River was still up, having stood her watch in the last third of the night, and she was seated on the overturned column, piecing something together on the sand in front of her. She gave the Doctor a pleased smile.<p>

"Good morning, Sweetie," she said.

"Good morning, Sweetie," echoed Jack, with a very annoying grin.

"_No_," said the Doctor, pointing a finger at Jack. "Absolutely not. And good morning, River."

"Not even if I give you a nice sausage?" Jack asked, spearing one on a fork and holding it out. River started to laugh. The Doctor scrubbed at his face and then ran his hands through his hair quickly before giving it up as a bad job.

"Bleccch," he said. "Sausage. Amy made me some once. In Scotland. I thought she was trying to kill me. Though in retrospect she was only seven." He levered himself up and went to sit beside River. "I wouldn't say no to a cup of tea, though."

"Sorry," said Jack. "No tea. Couldn't find any."

"But you found sausages? Here?" The Doctor looked around, but somewhat unsurprisingly failed to discover that a refrigerator had materialized in the night.

"Yep," said Jack. "Over there." He indicated the direction with his head. "A bit waterlogged, but basically okay. Maybe a week and a half old. Which is... weird."

"Hmm," said the Doctor. "Yes. And a week ago, this wasn't here. You see, just when I think things are beginning to make sense you have to go and present me with sausages. Mysterious island sausages. You're a hard man, Jack."

Jack grinned again. "I do my best."

River was regarding the both of them with amusement. "If you've finished entertaining yourselves," she said, "I've figured out where we are."

* * *

><p>The Doctor looked up again, gauging the progress of the water. They had at least another hour before it got high enough to detonate the explosives.<p>

_River really is very clever, you know. Though I wouldn't have expected any less from your daughter..._

* * *

><p>"All right, "said Jack. "Where are we?"<p>

"Have you ever heard of Germshel?"

The Doctor snapped his fingers. "Yes!" That was what he'd noticed about the columns yesterday. "Of course, of course, of course."

"No," said Jack. He moved the pan of sausages off the fire, then dragged up his own rock next to the overturned column and sat.

River assumed a lecturing posture. "Germshel was an island city on Metralubit, in the Fostrix galaxy. It's considered the primary inspiration for the myth of Atlantis, because the whole island disappeared, practically overnight. There was some evidence that it didn't sink – fishermen reporting lights in the sky, a mysterious wind – but no one ever knew what had become of it."

"And you think _this_ is Germshel?" Jack asked skeptically.

"I'm sure of it," River said. "See these columns?" She reached down and knocked on the overturned one they were using as a seat. "The buildings on each street are numbered, and the ones with Fibonacci numbers have a pair of columns flanking the doorway. That's Metralubit. I've never seen it anywhere else."

Another of the columns stood at the edge of their camp, marking the edge of a ruin that must have once been a small house. The Doctor pushed himself up and went to look at it, considering, then stuck his tongue out and licked it, just to be certain. "Yes," he said, and then, "Blecch!" He wiped off his tongue with the cuff of his shirt. "Even more blecch than sausages, that. Definitely Metralubit, though. Plus a bit of Earth salty ocean, but there would be." He turned around and let his gaze wander over the nearby buildings.

So this was Germshel, eh? Stupid of him not to have seen it immediately. The place was a bit of a dump, but interesting nonetheless. How had it gotten here?

"But how did it get here?" Jack asked, only a step behind.

"I've got a theory." River sat up a bit straighter. "You were telling me about your Rift in Cardiff, Jack. What if this came through one of those?"

"I thought you said it had come up through the ocean," Jack said. "And anyway, there's no residue. Things that come through the Rift, they're coated in artron energy. But this place isn't."

The Doctor opened his mouth to answer, but somehow River was faster.

"Suppose the Rift is in a deep-sea trench."

This stopped Jack cold.

"Yes," said the Doctor, taking up the thread. "Yes, yes. Think of it. It's a big ol' Rift at first, must be. It brings the city through." He found himself pacing, back and forth across the stretch of sand they'd cleared to sleep on. "But that exhausts it, blocks it up, squeezes the gap down to something like a trickle. Drip drip drip, all this other stuff comes through, all of this," he waved his hand expansively, "just piling up every which way. But then something else happens. An earthquake?"

"Yes," Jack said, nodding slowly. "Two weeks ago."

"That would have been enough," said River. "A big jolt, and the city gets shoved out of the Rift. Maybe there's a pocket of gas that gets released." She made a gesture indicating something billowing out from a central point. "It floats upwards. All the artron energy gets washed away."

"That... could work," Jack said slowly. "Yes."

"It explains the way all this junk is piled up, too," River said. "I couldn't put my finger on it yesterday, but it's... it's wave patterns. Eddies."

"On the beach," the Doctor said, nodding. "Things grouped together in their own little gyres." He made a swirling gesture with his hands, several inches apart and then spiraling inwards until his fingertips met. "Oh, you are brilliant." He beamed at River.

"The question is, though," said Jack, "who's been shooting at us?"

* * *

><p>River was squatted on a flat rock, dangling her fingers in the water and idly picking up bits of things as they flowed past. Periodically she would pull out something interesting, make a humming noise, and then drop it back into the water. The Doctor watched her for a few moments, then turned back to his writing.<p>

_Unfortunately, on our morning stroll we unearthed a number of rather inconvenient problems..._

* * *

><p>After breakfast they went exploring. The Doctor kept the sonic screwdriver out, periodically checking for any unusual technology, and though he noticed that both River and Jack kept their weapons ready, he decided not to say anything about it. They picked their way through the debris northward, towards the side of the island that Jack said he hadn't managed to get to.<p>

Now that he knew what he was looking for, the Doctor could see the patterns in the piles of wood and plastic and metal and stone, the way the heavier objects had settled into the sand and then everything else had been tossed and twisted around them, torn and broken by the forces of water. Waves – of course, it was so obvious! And yet it had taken River to figure it out. Not that she couldn't figure out such things, of course, but he ought to have seen it first. Perhaps he'd spent too long fixing the problems people caused for each other. He'd forgotten that sometimes they just happened, that sometimes there was a natural explanation.

He stepped over a stuffed toy Ood, then paused and stooped down to pull at the hilt of a Tritovore blaster which stuck out from between two large, silvery rocks. A moment's work told him that the blaster was irrevocably broken, and with a sigh he chucked it away, then stood up again as a disturbing thought occurred to him.

"I can't let Torchwood have this," he said.

"Have what?" said River. "That old blaster?"

"Any of it," the Doctor said. "Most of it's junk, yes, but some of it isn't. Some of it's dangerous."

"Doctor," said Jack, but the Doctor held up a hand.

"I can't— if it were just you, Jack, I'd—" He shook his head. "I know I've said otherwise before, but honestly, Jack. If it were just you, then I wouldn't be so worried. But a whole city's worth of debris cherry-picked from every which where in the universe? Who knows what else is here. And you're not going to tell me you'll be able to go through it all, Jack, no matter how long they give you. And they'll want you back eventually."

Now Jack said nothing, just looked away.

"_Jack_," the Doctor said. Jack raised his eyes, then shrugged.

"Eventually," he said. "But you're right. Even when I was in charge of Torchwood there were things I kept from them."

"So what are we going to do?" River asked.

"I don't know," said the Doctor. "I really don't."

Suddenly the sonic screwdriver burst into a high-pitched beeping. "What?" said the Doctor. He lifted it to his face, hummed, and adjusted several settings in rapid succession. The screwdriver's beeping continued, speeding up until the noise was almost one continuous whine, and then as suddenly as it had begun it stopped, leaving the three of them to blink stupidly in the ensuing echoing silence. The Doctor checked his readings again, and then a third time, just to be sure. "Oh, that's not good," he said. "Very not good, in fact."

"Sweetie," said River, sounding exasperated.

"Doc, out with it," said Jack.

"A Dalek," the Doctor said grimly. "Somewhere on this island there is a Dalek."

* * *

><p>The water was rising more quickly now, and the Doctor's shoes were wet clean through.<p>

"Doc," said Jack.

"Not yet," said the Doctor. But he did start writing a bit faster.

_Sometimes I wonder if Earth gives off some sort of signal, one that says, 'Conquering aliens, I am here and ripe for the picking.' Must remember to look for that at some point..._

* * *

><p>There was a moment of stunned silence.<p>

"You should go back to the TARDIS," the Doctor said. He could feel his hearts beginning to beat rapidly, adrenaline and fury racing through his veins in equal amounts. Daleks! How he hated them. "You should go back to the TARDIS right now, River. I'll handle this."

River made a disparaging noise in the back of her throat.

"I mean it," he said. "You don't know what we'll be dealing with."

"You're wasting time," she said. "I'm not leaving you."

He looked at her for a long moment – the set of her jaw, the fire flashing in her eyes. She'd figured out where they were before he had, and he clearly wasn't going to be able to get her to safety without a struggle. "All right. But you _do as I say_, understood?" At her nod, he continued. "Right. Since we haven't been shot at in the last eight hours, we can assume one of two things. Number one, it doesn't know where we are. Or number two, it doesn't care where we are, so long as we don't get too close."

"It didn't follow yesterday," River pointed out. "And it could have."

"So whatever it is it doesn't want us to see is somewhere on the west side of the island," Jack said. "That makes sense." He made a face. "Insofar as any of this makes sense. What the hell is a Dalek doing _here_?"

"It got stuck," the Doctor said. "That Rift of yours in Cardiff, it brings you people sometimes, doesn't it?"

"Yeah," Jack said. "Sometimes. They usually don't survive it."

"A Dalek can survive just about anything," the Doctor said sourly. "A trip through the void and some time spent at six thousand fathoms is practically a jaunt on Limnos 4 for them." He started to pace, then nearly tripped over six copies of _A History of Peas_ which were splayed out in the middle of the path, and made himself stand still. "The question isn't what it's doing _here_. It's what it's _doing_ here."

"Does it matter?" Jack asked. "What matters is that we can kill it. If we leave now, Torchwood can take care of that without coming anywhere near. We've got this cute little laser cannon now—"

"And if it's building another reality bomb?" the Doctor asked sharply. "Another time destructor? Do you have any idea what effect a laser cannon would have on something like that?"

"No," Jack admitted.

"Neither do I," said the Doctor. "And I'm not particularly excited to find out." He scrabbled his hands through his hair. "I need to know what it's doing," he said.

"So we get closer," River said, and tapped the sonic screwdriver with her index finger. "Which way?"

* * *

><p>"All right," said the Doctor, tucking the sheet of paper and his pen into the inside pocket of his blazer. "Set it off, Jack. Then get ready to run."<p>

_Now, don't panic, you two. I, of course, had everything under control..._

* * *

><p>Jack used the sonic screwdriver to unlock the door of the building, then carefully passed it back over his shoulder to the Doctor. They had followed the Dalek's trail west and north, carefully skirting the square they had passed through on the previous day, until a bit of triangulation revealed that the signal originated from this tall, pyramid-shaped building with an antenna perched atop its roof.<p>

The door made a faint scraping sound as Jack pulled it open, and he waited a moment before moving any further, listening with head cocked for any approach. The silence appeared to satisfy him, and he stepped forward into the dark corridor, the Doctor on his heels and River following. River pulled the door almost all the way closed behind her.

A wide path had already been formed through the debris, and the Doctor indicated they should follow it as far as it led. Eventually they came to a place where a hallway split off in two directions, both cleared, and Jack paused, cocking his head quizzically. The Doctor looked one way, then the other. He didn't want to use the sonic, not here, in case the Dalek was monitoring for any of its frequencies. Eventually he decided that the right-hand hallway looked marginally less-recently used and pointed in that direction. Jack nodded, and set off again.

They passed room after room full of debris – broken radio equipment, tree trunks, clothes, plastic toys, statutes of gods with three heads and nine arms, half of a bright-blue motor scooter sheared clean down the middle, a child's tea set, framed watercolor paintings of Paris, a diamond the size of Jack's fist. Eventually the cleared hallway ended at another door, this one open just a crack with yellow light streaming from inside. Jack pushed it slightly further open and then waited cautiously, but there was no sound from inside. He stepped through.

The room had been set up as a radio facility, able both to send and to receive. Across the far wall was an array of screens that were set to monitoring incoming signals. On the left wall were the transmitting controls – several microphones, a sound board, and more screens, one showing signal power and another showing possible sources of interference from the atmosphere.

"Hmm," said the Doctor, crossing over to the wall where the transmitting equipment was running with a low, steady hum. "They're sending a signal. Look at this." Jack and River came to stand on either side of him, peering down at the screen. "Very crude," the Doctor said. "Weeeelllll, I suppose it'd have to be. They've cobbled it together, d'you see? Scavenged what they could from whatever they could find." He could almost have admired the ingenuity of it all, if it hadn't been done by a Dalek. "But what sort of signal?"

"If you were a Dalek, what would you do?" Jack asked.

The Doctor made a face. "What a horrible thought." He bent down and un-fastened a panel, then started pulling at wires, breaking the connection between the microphone and the display. "But we don't have to guess. Hand me one of those speakers." He gestured vaguely, and a moment later River held a speaker into his line of sight. "No," he said, without looking up, "no, no, no, _not_ that one, honestly—" but River was already handing him a different speaker. "Yes, yes, yes, good." He stripped the end of the speaker wire and twisted the two wires together, then sonic-ed them briefly to force the connection to form. Once it was solid, he jammed the panel back in place, then reached for the playback controls.

There was a whirring noise from the corridor. The Doctor startled, then turned towards the door frantically. "Hide, hide," he hissed at Jack, who was already pulling River behind the door so that they would be out of sight when it was opened. There was only space for two people. The Doctor looked around frantically, but there was nowhere else to go. A moment later the Dalek pushed open the door, then stopped short when it saw him. There was a moment of fraught silence.

"INTRUDER," said the Dalek. "INTRUDER. EXTERMINATE."

* * *

><p>The explosives were set in three batches, and they sent a series of successive shockwaves rolling through the rock beneath. River stumbled, but the Doctor caught her arm before she could fall completely, and a moment later she was running steadily again at his side.<p>

* * *

><p>"Can't we talk about this like civilized peop— er, beings?" the Doctor asked, but even as he said it he was in motion, pushing up with the balls of his feet to lift himself into the air, up, up, and then he landed behind the Dalek and turned, grabbing at its eyestalk.<p>

The Dalek twisted in his grasp, metal sliding slickly beneath his hands. "YOU WILL BE EXTERMINATED," it said. The Doctor shoved at it, and managed with his third heave to tilt it sideways, pressing the eyestalk back around towards the doorway.

"Jack!" he cried, and then, "River! Dammit, will one of you just—"

"Hold _still_, Sweetie," said River, exasperated.

"I'm _trying_," said the Doctor. He jammed his foot under the upturned edge of the Dalek's base and heaved it over further. It fired a bolt of electricity that sizzled between River and Jack, just missing River's head, and then River and Jack fired together in quick succession, two sonic blasts straight into the eyestalk's lens.

The Dalek made a horrible moaning noise, the sound of metal grinding on metal, and then went silent and still. The Doctor held on for another long moment, then let go. It toppled over onto the floor with a clang, its eyestalk emitting a thin curl of smoke.

"Best honeymoon ever," River said, and holstered her blaster with a swift, precise twirl.

"_Honeymooon_?" Jack asked incredulously. "You didn't tell me this was your _honeymoon_." He grinned. "If I'd known, I'd have brought you some supplies."

The Doctor put one hand over his face and tried not to laugh.

* * *

><p>They made it to the TARDIS just as a wave crested over the island's highest point. Jack slid inside last and shut the door behind him, though not before cold rivulets of water sloshed over the door jamb and through the grating down into the wiring below. Something hissed and fizzed.<p>

"Sorry, girl," the Doctor said, rubbing one of the railings. "I'll clean that up in just a minute."

* * *

><p>They dumped the Dalek's body in one of the rooms off the main hallway, burying it beneath a huge tapestry that still hadn't dried completely after being submerged in the ocean for so long. Then they went back to the radio room and listened to the Dalek's message.<p>

"I HAVE BECOME SEPARATED FROM MY PLATOON AND REQUEST RETRIEVAL. RECONNAISANCE HAD BEEN PERFORMED ON THIS PLANET ACCORDING TO STANDARD PROCEDURE AND I FIND IT SUITABLE TO BE CONQUERED. MY CURRENT COORDINATES FOLLOW."

The message repeated twice before the Doctor shut it off with one angry swipe of his hand.

"Will they come?" River asked quietly.

"I don't know," he said. "There shouldn't be any Daleks left – I've destroyed them all. But somehow they keep slipping through the cracks. They just _won't die_." He huffed out a sigh, then rubbed his chin. "This wasn't the only thing it was working on. We'd better see the rest."

'The rest' turned out to be a half-finished teleportation pod, built in what had previously been one of the building's public bathrooms. Scraps of old tires lined the walls, wires hanging from between them, and the marble of the floor was covered in flat metal pieces welded together at the seams.

"Hmm," said the Doctor, tugging on each of the wires in succession. "Yes, yes, no, no, ooh – definitely no, shoddy workmanship there, yes, yes, no, yes. But where was he going to get the rhondium?"

Jack stood in the center of the room and turned a slow circle. "Guess he didn't trust his mates to come and get him after all."

"Even Daleks don't trust Daleks," the Doctor said. "But yes, yes, this is good, this is good, I can work with this."

"To do what?" River asked.

"To sink the island."

* * *

><p>He flicked off his shoes and socks, then dumped them into the wardrobe room, which had conveniently appeared as the first door off the main hallway. Bare-footed, the Doctor grabbed a towel and pulled up the grating, wiggling his way underneath to mop up the remainder of the water there.<p>

"All better?" he asked, and felt the TARDIS give a pleased throb of thanks. He climbed back up and replaced the grating, then lay on his back and pulled the scrap of paper and the pen out of his pocket.

_All in all, it was quite an adventure. See you soon._

He hesitated a moment, then added one last line.

_Love, the Doctor_


End file.
